Post-Employment Benefits - Summary of Weighted Average Principal Assumptions Used to Determine Defined Benefit Obligation (Parenthetical) (Detail)	Oct. 31, 2020	Oct. 31, 2019
Canada plan [member]
Disclosure of defined benefit plans [line items]
percentage of weighted average salary growth rate	2.00%	2.30%

The expected rate of salary increases used as a significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit plans [member]; Defined benefit obligation, at present value; Actuarial assumptions [member]]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2019-01-01
-Paragraph 144
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2019-en-r&anchor=para_144&doctype=Standard
-URIDate 2019-03-27

Name:	ifrs-full_ActuarialAssumptionOfExpectedRatesOfSalaryIncreases
Namespace Prefix:	ifrs-full_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant